Really from chapter 23 to the end, the novel can be divided between two main events: the Wilks family scandal and the Phelps’ farm ordeal. In the Wilks family ordeal, the King and Duke impersonate Mr. Wilks and a servant in order to claim an inheritance. It is from there, Twain examines the gullibility of society through the acceptance of the Wilks family. However, in order to protect the family, Huck hides the money the King and Duke try to steal. Huck and Jim fail to escape toward the end of this ordeal.
Next in the Phelps farm incident, Huck must rescue Jim who has been sold out by the King and Duke, ironically, to the relatives of Tom Sawyer. Tom arrives and intervenes by introducing a ridiculous plan for Jim’s escape. The whole plan is a one of situational irony. Rather than planning a quick escape, Tom, the embodiment of fantasy/romanticism, conjures up various escape tactics depicting adventure/prison novels he has read. Later, Tom is shot trying during the escape, and he tells Huck that Miss Watson, who had died, freed Jim, and had mentioned Jim’s freedom in her will. Later on, Huck learns that it was “Pap the dead man in the house floating down the river”(Enotes, Huck Finn). Finally, Huck heads to "light out for the Territory ahead of the rest”(Enotes, Huck Finn). Huck does not want to be civilized by humanity.
ENotes provides great chapter-by-chapter summaries for many books and stories. I have provided a link below that will lead you to a link where you can find chapter summaries of "The Adventures of Huckleberry Finn". Also, I provided links that talka about the themes that are apparent in the book, along with Twain's writing style. Take a look, and I hope that helps!